玄武岩-粗聚丙烯纤维钢筋混凝土管力学性能

针对实际工程中钢筋混凝土管节管壁易产生裂纹、影响工程质量问题,鉴于玄武岩纤维与粗聚丙烯纤维能够明显改善混凝土的抗拉、抗裂等力学性能,设计制作了一组普通钢筋混凝土管节B0P0和一组混掺玄武岩-粗聚丙烯纤维钢筋混凝土管节B2P4,进行室内三点试验,对比试验过程中两组管节的开裂破坏形态和荷载 位移曲线,并利用ABAQUS软件建立钢筋混凝土管节数值分析模型,研究不同纤维配比和钢筋配置对钢筋混凝土管节受力性能的影响规律。研究结果表明:相较于B0P0,混掺玄武岩-粗聚丙烯纤维钢筋混凝土管节B2P4承载力提升了30.19%,管节表面裂缝宽度明显减小,阻裂增韧效果好;数值模型与试验结果的误差在5%以内,能够合理预测管节的破坏过程、荷载 位移曲线和极限承载能力,并通过数值模拟确定了混掺玄武岩 粗聚丙烯纤维时的纤维最佳配比和合理钢筋配置。

Mechanical Properties of Basalt-Coarse Polypropylene Fiber Reinforced Concrete Pipe

In practical engineering, reinforced concrete pipe section is easy to crack, which affects project quality. In view of the fact that basalt fiber and coarse polypropylene fiber can obviously improve the tensile and crack resistance of concrete, a group of ordinary reinforced concrete pipe B0P0 and a group of reinforced concrete pipe mixed basalt and coarse polypropylene fiber B2P4 were designed and manufactured. The cracking failure modes and load-displacement curves of these two groups of pipe were compared in the test process, and the numerical analysis model of reinforced concrete pipe joints was established by using ABAQUS software, studying the influence of different fiber ratios and reinforcement configurations on the mechanical properties of reinforced concrete pipe. The results showed that, comparing with ordinary reinforced concrete pipe B0P0, the bearing capacity of reinforced concrete pipe B2P4 mixed with basalt and coarse polypropylene fiber was increased by 30.19%, and the crack width of pipe surface decreased obviously. The cracking resistance and toughening effect were obvious. The error between the numerical model and the experimental results was less than 5%, which can reasonably predict the failure process, load-displacement curves and ultimate bearing capacity of the pipe. The optimal proportion of basalt and coarse polypropylene fiber and the reasonable reinforcement configuration were also obtained by the numerical simulation.